Self-stripping wire twister hook for wire balers



Oct. 1, 1968 w. K. RALSTON ET AL 3,403,619

SELF-STRIPPING WIRE TWIST/3R HOOK FOR WIRE BALERS Filed Oct. 21, 1966 FIG.

/o\ 3/ F/G.2.

//\N/ 3 3/ 2/ 17 29- /7 A 28 W 3/ 20 2 r 22 29 /8 24 28 44 25 1 2O 25 19A 27 I3 22 /7 30 30 INVENTORS a WlLL/AMKRALSTON- 30 CHARLES e. BARF/.ELD

ATTY

United States This invention relates to a twisting mechanism of the general type used in hay balers and more particularly to an improvement in a twister hook for such twisting mechanism.

The preferred embodiment of the present invention, as disclosed herein, contemplates that the novel twister hook be incorporated in a twisting mechanism of the type shown in the Raney Patent 2,513,967 issued July 4, 1950. In the twisting mechanism disclosed therein, a twister hook is used for twisting the ends of a strand of wire encircling a bale formed in a baler. At the conclusion of the twisting phase, a stripper finger is actuated forcing the twisted wire from the hook. The use of a stripper finger as the means for stripping the twisted wire from the hook is undesirable because it increases the complexity of an already complex mechanism. For example, the stripper finger must be actuated at precisely the right moment in the sequence of twisting operation. This requires modification of the other components of the mechanism in order that the stripper finger coordinate therewith. Furthermore, the stripper finger must be precisely adjusted to travel far enough to dislodge the twisted wire from the hook.

Obviously then, a self-stripping twister hook, that is, r

a hook that requires no additional equipment for dislodging the twisted wire therefrom, reduces the complexity of the twisting mechanism and simplifies the twisting operation.

It is, therefore, an object of the present invention to provide a wire twisting mechanism having a selfstripping twister hook.

Another object is to provide a twister hook which is rotatable in a given plane for twisting and pivotable to a stripping position. 3

Still another object is to provide a twister hook having a pivotable beak, wherein the pivotal movement of said beak is characterized as snap-acting.

These and other objects of the present invention will become apparent to those skilled in the art as a preferred embodiment of the invention is disclosed in the following specification and claims taken in conjunction with the drawings in which:

FIGURE 1 is a fragmentary side view, partly in sec tion, of the novel twister hook contemplated by the present invention showing the twister hook in the twisting position; and

FIGURE 2 is, similarly, a side view of the novel twister hook but shown in its stripping position.

The preferred embodiment of the present invention as disclosed herein shows the novel twister hook incorporated in a wire-twisting mechanism of the type shown in the previously mentioned Raney patent. However, it should be understood that this is for illustrative purposes only in order to show the environment in which the novel hook operates, and that the novel features of the hook may be employed in other types of twisting mechanisms.

Referring to FIGURE 1, the hook designated as comprises generally a shaft 11 mounted for rotation in a housing 31 by any suitable means, such as that shown in US. Patent No. 2,513,967, and a beak assembly 12.

The =beak assembly 12 is particularly characterized as atent O ice having a connection member 14 and a beak member 13 which projects laterally with respect to the axis of the shaft 11. The connection member 14, secured to a dependnig member 11a from the shaft 11 by pin 15, pivotally carries the beak member 13. The shaft 11 carries at its upper end (not shown) a bevel gear (not shown) which in accordance with the principles of the Raney patent provides the means for driving the twister hook 10. A leaf spring 18, having a curved end 20 affixed to the connection member 14 as at 21 and an opposite end 19 secured to the beak member 13 at 19a, provides means for pivotal movement of the beak member 13 about an axis designated by 22. Mating guide surfaces 16a and 16b, formed respectively on the connection member 14 and the beak member 13, adds rigidity to the assembly and provides for a smooth pivotal movement of the beak member 13 about the axis 22. Note that the sectional form of the arcuate surfaces of 16a and 16b is that of a circular are about a center axis concurrent with the pivotal axis 22.

The leaf spring 18 biases the beak member 13 into a wire twisting position as shown in FIGURE 1 wherein a fiat radial surface 17a formed in the beak member 13 abuts a corresponding flat radial surface 17b formed in housing 31.

The twisting position of the beak is primarily maintained by a spring assembly comprising a ball 26 and a compression spring 25. A recess 24 formed in the connection member 14 and projecting radially inwardly from guide surface 16b toward pivot point 22 is aligned with a corresponding recess 23 of slightly reduced diameter formed in the beak member 13 and projecting radially outwardly with respect to pivot point 22 from guide sur face 16a. The diameter of the ball 26 is such as to permit free axial movement but to preclude lateral movement within the confines of recess 24. The compression spring 25 received in the recess 24 forces the ball 26 outwardly into an engagement with an annular shoulder 27 of recess 23.

Thus it is seen that in the twisting position, the bulk of ball 26 is lodged in recess 24 and a small arcuate portion protrudes into recess 23, and that the ball 26 is movable against the bias of compression spring 25 radially inwardly with respect to pivot point 22. Downward movement of the beak member 13 forces the ball 26 radially inwardly against the compression spring 25. Once the ball is completely dislodged from the recess 23, it rides on guide surface 16a and its effect on further pivotal movement of beak member 13 becomes negligible. The beak member 13 is further pivotable against only the bias of leaf spring 19 to a stripping position as shown in FIGURE 2. The downward pivotal movement is limited by a flat stop 28 formed on the upper part of the beak 13 which abuts a flat radial surface 29 formed on housing 31.

The strength of the spring 25 is selected so that the beak member 13 is maintained in the twisting position during twisting operation.

In operation, assume that a wire 30 encircling a bale (not shown) has its ends 30a and 30b intertwisted by the hook 10 in the twister position of FIGURE 1 in accordance with the operation of a twister device described in US. Patent 2,513,967. As the formed bale is forced out of the baling machine (not shown) by a succeeding bale, the tension in wire 30 looped over beak member 13 imparts a downward force on the beak member 13. The downward force is opposed primarily by the shoulder 27 engagement upon ball 26 and to a limit extent 'by the bias of the leaf spring 18. At a predetermined downward force created by the wire tension, the shoulder 27 moves downwardly forcing the ball 26 inwardly against the compression spring 25, causing the beak member 13 to snap to the stripping position as shown in FIGURE 2. Once the twisted portion of wire 30 is stripped from the beak member 13, the upward force of the: leaf spring 18 snaps the beak member 13 back to the twister position.

Obviously many modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. In a wire twister mechanism of the type used to join opposite ends of a wire strand encircling a bale formed in a baling machine by intertwisting the ends, a twister hook comprising a rotary element rotatable about a fixed axis, and

a twister element projecting laterally from the said rotary element and co-rotatable therewith, said twister element normally disposed in one position for rotation with said rotary element, and movable relative to the said rotary element to another position for stripping wire therefrom.

2. The twister hook as recited in claim 1 wherein the said twister element is pivotally mounted on said rotary element, said twister element pivotable about an axis disposed transverse to the said fixed axis.

3. The twister hook as recited in claim 2 wherein the said twister element is pivotable about an axis disposed transversely to and radially removed from the said fixed axis.

4. The twister hook as recited in claim 1 and further characterized by a biasing means for biasing the said twister element in the said one position for rotation.

5. The twister hook as recited in claim 4 and further characterized by a second biasing means for maintaining the twister element in the said one position for rotation, the said second biasing means being operative only when the said twister element is disposed in the said one position for rotation.

6. A wire twister hook comprising a shaft rotatable about a fixed axis;

4. V I p a beak member projecting laterally with respect to said connection means interconnecting said shaft and said beak member, said beak member co-rotatable with said shaft, and pivotally movable about a pivot axis transverse the fixed axis between a first position for rotation and a second position for stripping wire therefrom; and

biasing means for biasing said beak member in .said

first position for rotation.

7. The wire twister recited in claim 6 and further characterized by a second biasing means for maintaining the said beak member in said first position for rotation.

8. The wire twister recited in claim 6 wherein the said first biasing means includes a leaf spring interconnecting the said beak member and the said connection means; and the said second biasing means includes a latching device carried by said connection means and engageable with said beak member, the said latching device being operative only when the said beak member occupies the said first position for rotation.

9. A rotary wire twister comprising a shank structure;

a twister element pivotally mounted to said structure for swinging movement between a twisting position and a release position;

means biasing said twister element to said twisting position; and

latch means releasably holding said element in said twisting position and releasable attend-ant to a pull of a predetermined magnitude being exerted on the element.

References Cited UNITED STATES PATENTS 40 LOUIS O. MAASSEL, Primary Examiner. 

1. IN A WIRE TWISTER MECHANISM OF THE TYPE USED TO JOIN OPPOSITE ENDS OF A WIRE STRAND ENCIRCLING A BLADE FORMED IN A BALING MACHINE BY INTERTWISTING THE ENDS, A TWISTER HOOK COMPRISING A ROTARY ELEMENT ROTATABLE ABOUT A FIXED AXIS, AND A TWISTER ELEMENT PROJECTING LATERALLY FROM THE SAID RORARY ELEMENT AND CO-ROTATABLE THEREWITH, SAID TWISTER ELEMENT NORMALLY DISPOSED IN ONE POSITION FOR ROTATION WITH SAID ROTARY ELEMENT, AND MOVABLE RELATIVE 